BBC Red meat 'cancer threat': Eating red meat (including pork and lamb as well as beef) introduces a potentially dangerous molecule to the body which could cause cancer, researchers say

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>BBC DAILY E-MAIL: UK EDITION

>Tuesday, 30 September, 2003, 08:00 GMT 01:00 US/Pacific

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> * Red meat 'cancer threat' *

>Eating red meat introduces a potentially dangerous molecule to the

>body which could cause cancer, researchers say.

>Full story:

>http://news.bbc.co.uk/go/em/-/1/hi/health/3149062.stm

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Red meat 'cancer threat'

Eating red meat introduces a potentially dangerous molecule into the

body tissues, according to researchers.

 

Scientists from the University of California in San Diego

believe it could cause heart disease and cancer by triggering a

harmful immune response.

Humans cannot produce the molecule - a type of sugar - but it

occurs at high levels in lamb, pork and beef.

The research is published in the Proceedings of the National

Academy of Sciences.

 

Human volunteers

 

Several studies have associated red meat diets with cancer

and heart disease.

But these have focused on saturated fats and chemicals

produced during the cooking process.

 

 

It could be that the damage only builds up over years

Professor Ajit Varki

 

The new research focuses on a sugar called

N-glycolylneuraminic acid (Neu5Gc).

Tests on three human volunteers - all members of the research

team - confirmed that if the sugar is present in the diet, it is

absorbed into body tissues such as the blood vessels.

The tests also suggested that because the molecule is not

naturally present in the body, it is viewed as an invader by the

immune system, which is sparked into action.

Lead researcher Professor Ajit Varki said the molecule was

almost certainly not immediately toxic, and it was possible that

humans had built up a tolerance after hundreds of thousands of years

of eating meat.

" It could be that the damage only builds up over years, " he said.

" However, we are now living longer and the question arises

whether the gradual accumulation of Neu5Gc and the simultaneous

presence of antibodies against could be involved in some diseases of

later life. "

 

Animal transplants

 

Professor Varki said the molecule may be one of the main

obstacles in the path of developing animal-to-human organ transplants.

Scientists are trying to find ways to stop the powerful

immune response that occurs when a pig organ is put into a human.

The three scientists who were involved in the study drank a

solution of Neu5Gc purified from pork.

Tests showed that most of the molecule was eliminated by the

body, but small amounts were absorbed into the body.

About two days after ingestion, Neu5Gc levels were raised two

or three-fold.

By four to eight days, levels had dropped almost to their

original level.

 

Good evidence'

 

Dr Julie Sharp, from Cancer Research UK, said a third of all

cancers were linked to diet.

" There is good evidence that a diet rich in fruit, vegetables

and fibre and low in fat and red meat can reduce the risk of the

disease.

" However these results are preliminary and were obtained from

analysis of only three individuals.

" Large-scale population studies would be needed to prove if

this molecule has any role in human disease including cancer. "

A spokesman for the British Dietetic Association told BBC

News Online: " We would encourage people to eat a balanced diet based

mainly on starchy carbohydrates, fruit and vegetables with small

amounts of protein from a variety of sources, including diary,

vegetables, meat, fish and poultry. "

 

 

Story from BBC NEWS:

http://news.bbc.co.uk/go/pr/fr/-/1/hi/health/3149062.stm

 

Published: 2003/09/29 23:39:57 GMT

 

© BBC MMIII

 

 

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